Conventional turbomachines (also referred to as turbines), such as steam turbines (or, steam turbomachines), generally include static nozzle assemblies that direct the flow of working fluid (e.g., steam) into rotating buckets that are connected to a rotor. In steam turbines the nozzle (or, airfoil) construction is typically called a “diaphragm” or “nozzle assembly” stage. Nozzle assemblies are assembled in two halves around the rotor, creating a horizontal joint.
In a double-flow (or dual-flow) steam turbine, inlet steam is directed through an inlet passageway and divided (split) into two axial passageways connecting with a first and second side of the turbine. Conventionally, the flow is divided using a structure called a flow splitter. After the steam flow is divided, the steam flows axially in opposite directions through the nozzle/bucket stages of each side of the turbine.
Some conventional flow splitter designs include large, heavy and costly structures which include two mirror image-like axial halves that are bolted together through large flanges. The bolt is traditionally aligned on an inside radial surface of the axial halves, between the flow splitter and the rotor body. Each half of the flow splitter is conventionally machined from a large forging, which results in a significant amount of stock material being wasted during the forging process. In other conventional flow splitter designs, a unitary splitter structure is formed and then machined to include hooks for engaging complementary hooks on the diaphragm and maintaining a radial and axial position of the flow splitter. However, the process of forming this unitary structure, e.g., via forging and subsequent machining, can be complicated and time consuming. Additionally, the hooks of these conventional flow splitters also react with a portion of the axial pressure force on the nozzle stage, which can cause maintenance related issues after the turbine has operated for an extended period.